Jet spoiling means for aircraft gas turbines



May 5, 1953 A. R. D. ROBSON ET AL 2,637,164

JET SPOILING MEANS FOR AIRCRAFT GAS TURBINES Filed March 8, 1946 I Fig.1

I nvnlons lorney y 5, 3 .A. R. D. ROBSON- ET AL 7 2,637,164

JET SPOILING MEANS FOR AIRCRAFT GAS Filed March 8, 1946 4 Shets-Sheet 2Fig.3. 2: 22 2 4 I #:LI 28\ 22B ZI 4 A ltorney A.'R. D. ROBSON ET AL JETSPOILING MEANS FOR AIRCRAFT GAS TURBINE-S May 5, 1953 w h ama m a m 3 Zpn 2 I h KEN ms; y

m 0 BR May 5, 1953 A. R. D. ROBSON ET AL 2,637,164

JET SPOILING MEANS FOR AIRCRAFT GAS TURBINES 4 Sheets-Sheet 4 FiledMarch 8, 1946 4 In uentor-s OEI/EPEUX Patented May 5, 1953 ArthumRnWn":lIevereux dom-En lansh Afimlicatibn-MfircliiS} 1946SriaTNbLGEfiIISj meme-Britain Marat-22,1945,

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The invention; reiatem tor gas: turbineengines forruseiOIIIJfiJIYCIflLffiI; forsjets" pnopu1sion';and' itsp lm irya, Objectisntoi .proyide;= new, and improved'i; meansifor; What-t iis known:asefjetespoflingf that 1 51113 2 57; the: deflectionxzofthe propulsivejet-tin 5 web swarms to remove n-reeuce-its api'opulsivei efiectwanmmayhuaily reverse itzinthe: senseiofga-fierding vex-thrust Jertplopel lfifi:aircreftzareiapts ,beiaerodynahi Veahyycleanzemd: itgis An; their:nature; that-, even-;; the: small thrust 1 0 which is generated atidling speedsrofl engines may; be an embarrassment; for example, whenapproaching ito. land: It-- therefore becomes desirableto accordemeansfonredueingsuehidling teg er iitensions-tfiA which-aejresarcuathruster; even:pmmdmsice-ne ativethrust;- that: fliz-irizw'passesetefinineg means; to-si-sisidea eis;t0,;.say;; thr-ust1in-theopnositedirectiqn to that: usuallyyrequiredi for propulsion, Ther enditiens:of;operation10f anywdevieeciosely, associated with: ajet pipeaof ,anetircraft: aregusualiythosevof com pgaraitivelyy high" temperature the;necessity fer; lightness-of 1weight, conformityg'with streamlinedforms-5 of; aircraft! structuregand during normei; operation very.highqvelocities offlow.

It is particularly; important: th2 t;,W-h6n1 not ,in; operation the jetspoilingmeans shall nottinaany way; impede ,-the flow of the: workingfiu-id end; that when in use-itisr-p'referred'thetethe,change; in.direction: of the Working, fluid. should; be:- brought;aboutigradually;so thatiif usedgforzbre'ksiDg.: p L1l-"QOSES.;- i. .e., I to in roduceia negative thrust, theerhish initial speedof. the working; fluid toywards: the nozzle? of theaiet. pipe- Wili -be1flma-intained. -to providethe mosttefiicient brsiking ef-pfeet.

The chief pbifieteofthevinvention therefore is to ;.ev01,vejet;spoilingmeanss which. will satisfy, the; above requirementss Theinvention isiilustrazted by the eizcomn w, u ins,diagrammaticfldrawinge, which show. it in three, examples.

Figures land 2,'respective1y an end view and a, sectional view,showhwhat; may, be its simplest. form;,

Figures -3 andehoth sectional uviewsvrand 5 and 6, which arerespectively. an end ,view.and a per.- spective .of; adetaihflcollectively, illustrate a, sec.- 0nd embodiment;

Figure ,7' is asectional elevation-of "a; third em, bodiment;

Figure 8 is a; perspective diagrammatic view of an aircraft having'a-gas turbine aero-engine pro vided with jet spoiling means accordingto the-in 'vention.

m the case ofFigsul and 2;" the jet p p litsel-ff mutheipart70fitS'f16ng-th with which we are concernect) octagonal-insectiom for ease jot-"com Uponeach hinseaist ivetellyvmenntedm flaw-sensisting one? trianeuiarzdefieeton portiem normally lies in and closes.aacerresponchn etrie; sngularzaperturea i innthessideel Themortionsztfijectech, workings flzuidg, outwards and for-w (relative-ate the direeioniofz flishtfiproducl ne ative hrustnn fbraking." Theiextensions-taAsmay-gin some cases itebeingi aimaitter of selection a of; dimensionsrend .Of geometry? be so "arran ed that-When they; areoperatiyetheir at-,3 ecent meesins; meetvpresenting a .continuolis annular. wall, to the.deflected: fluids-.2. In. other-cases, SLLQI'L as... that lshown, they;Dfiesenti avipettern :such as that of Fig. 1,;whichisnot deemecisto beSEiiIiOllSlYgidiS-w andvanta ceouspbeeause itis improbable.thatrhigllsefiiciency will oe sought in-thesnegetitethrust; case. and the igapsihetwteen adjetcent'uextensiohs 3A,-,wi1i probably create,stronssturbulence, ,wh'izth-v at leasttspoils the.jei Itwiillbie.observeri...(Fi 2" especially) that the ,flaps,;3 jcangbesarrangedstogmeet dike ;a;pyramiei and thus nomnletely' ebturatem thenormal,propulsive". flow. in. the; pipe. This; scheme has stheflpossib'ility011a, high degree of J. balanceeonwthevmoving elements; sethst operatein ,forces.-mey. ;bje mogierate.,., The. .refereneeinu-z tion; 1 22coa'xiazliy; surrounding: extension; 121 end: connectedrto the end ofpipeieiby az'shortqfrnste-s con-ica-lzmeckd 0A2; At itsreareendiisxmfurthers? mounting spams-which is :aisora passa e-defining;

section, which interconnects the end of 22 with the skin 23 of a nacelleor fuselage. By these means the section 22 is mounted. In its wall areformed slots at 223 for the sliding passage of rods 2|A which, fixed tothe extension 2|, control the fore and aft movement of the latter, andoutside the section 22 slidably carried, is a sleeve 24 which moves withthe rods 2|A and which serves to seal the slots 223. The pipe section 2|carries towards its rear end (where is the final propelling nozzle thetrailing end portion of the nacelle, in the form of a skin 26, profiledto correspond with the shape of the skin 23. Within the forward end ofthis skin 25, is an annular, arcuate section, wall 21 whichinterconnects the skin 26 with the section 2| to mutually support theseelements. The wall 21 also defines an outward and reversal fluidpassage, complementarily to the part 22A. There may be a further annularcascade vane or ring 21A, to render the direction of the fluid moreefficient. It will be apparent by comparing Fig. 3 (normal condition)and Fig. 4 (condition for spoiling and reversal), that rearward movementof the section 2| by any suitable motive means applied to the rods 2|A,causes an annular opening to appear between the pipe 20 and section 2|,and simultaneously between the skins 23 and 26 in the manner of asliding door, the annular passage between 2| and 22 then being availablefor diverted fluid.

Within the pipe 22 near the neck 20A, is a series of flaps 28 (see Fi 6)each of arcuate section, flanged at its parallel edges for stiffness.These are carried pivotally on a suitably bent hinging rod 29 which issupported through members 29A, by the sections 22. When the section 2|is Withdrawn rearwardly these flaps fall inwards towards the interior ofthe jet pipe and partially obstruct the flow therein, simultaneouslydiverting fluid through the opening between 20 and 2|, and thus into thepath above described. When the section 2| is returned forwards, itsupstream edge automatically pushes the flaps out to their idle position.The flaps may be spring loaded (as by springs indicated at 30) to thiseffect.

Fig. '1 illustrates a third form of embodiment in which a jet spoilersystem is combined with a variable nozzle jet. In this case a fairing orbullet 23 is mounted concentrically in the mouth of the jet pipe 20which is bell mouthed at 29 to maintain a constant cross-sectional areafor the annular gas outlet. Towards the downstream end of the bullet 28are provided a plurality of deflection plates 36 adapted to pivot aboutthe periphery of a tubular ring 3| attached to the bullet 28 andco-operating with levers 32 and arranged so that in the closed position,as shown in full line, the plates 30 are held in corresponding aperturesin the bullet wall, and in the open position as shown in broken line theplates obstruct and divert the normal jet flow in the direction shown bythe arrows.

The rear part 28A of the bullet 28 is movable axially by means of a highspeed electric motor 33 driving through suitable reduction gear 40, 4|,to operate the outer jack screw 34 of a pair of co-axial jacks 34, 35,which in turn operates in casing 42 thus moving said casing axiallytogether with rod 43, ring 3|, and part 28A simultaneously. The plates30 then open and divert the jet flow (as shown by the arrows) throughthe space between the parts 28 and 28A. Means maybe provided (forexample a limit switch in- '4 corporated on the jack) to cut out themotor when the fully open position is reached and similar means may alsobe provided for the fully closed position.

A variable area nozzle effect is provided in that the whole bullet 28 isalso capable of axial movement. This is effected by means of an electricmotor 36 which operates the inner jack screw 35 and thence moves casing31 rigid with support 38 which is itself rigid with bullet 28. To allowfor this movement slots 39 are provided in the bullet wall and sealed byflaps 44. Operation of motor 36 can thus move the whole bullet in thejet pipe 20, and thus give a variable area nozzle effect. The strut ishollow for the admission of cooling air which may be led in fromatmosphere by an external scoop and flows in the direction indicated bythe broken arrows.

Figure 8 is a perspective diagrammatic view of an aircraft in thefuselage 46 of which is fitted a gas turbine aero-engine comprising acompressor 41 delivering air which after being injected with fuel andbrought to combustion in combustion chambers 48 drives a turbine 49which itself drives the compressor 41, the hot gases being then ejectedto atmosphere through a jet pipe 50 to produce thrust. The jet spoilingapparatus according to the invention is attached towards the downstreamoutlet of the jet pipe 50.

We claim:

1. In an aircraft gas-turbine plant fitted with a jet pipe for therearward efflux of a stream of the working fluid as a propulsive jet,and

thrust-spoiling means associated with said jet pipe, comprising, incombination, an upstream pointing deflector associated with said jetpipe, guide means located downstream from said deflector and without therearward path of the said set to define a path for the working fluidchanging from the rearward direction to a thrust-spoiling direction,said guide means being movable from inoperative to thrust-spoilingposition and when in thrust-spoiling position having its exit directedradially outwardly from said jet pipe, means mechanicallyinterconnecting said deflector and said guide means, and means formoving said guide means to thrust-spoiling position and the upstream endof said deflector into and progressively across said stream to positionsin which it progressively decreases the cross-section of therearwardly-directed jet while at the same time deflecting some of theworking fluid rearwardly into the said guide means.

2. In an aircraft gas-turbine plant with a jet pipe and thrust-spoilingmeans arrangement as set forth in claim 1, a separate casing disposedabout the axis of the jet-pipe forming a passage and enclosing saidguide means, a closure means in said casing which can be opened topermit access of said passage to the atmosphere, and anoperating-connection between said closure means and said deflectorconstraining them to move together, said closure means being opened asthe deflector moves into and across the stream.

3. In an aircraft gas-turbine plant fitted with ajet pipe for therearward efilux of a stream of the working fluid as a propulsive jet,and thrust-spoiling means associated with said jet pipe, comprising, incombination, upstream pointing deflector means mounted around the axisof said jet pipe, guide means disposed around the axis of said jet pipedown-stream from said deflector and located Without the rearward path ofthe said jet to define a,

path for the working fluid changing from the rearward direction to athrust-spoiling direction, said guide means being movable frominoperative to thrust-spoiling position and, when in thrust-spoilingposition, having its exit directed radially outwardly from said jetpipe, means mechanically interconnecting said deflector and said guidemeans, and means for moving said guide means to thrust-spoiling positionand the upstream end of said deflector into and progressively acrosssaid stream to positions in which it progressively decreases thecross-section of the rearwardly-directed jet while at the same timedeflecting some of the Working fluid rearwardly into the said guidemeans.

4. In an aircraft gas-turbine plant fitted with a jet pipe for therearward eiiiux of a stream of the working fluid as a propulsive saidjet pipe having at least one apertured part therein, and thrust-spoilingmeans associated with said jet pipe, comprising, in combination, anupstream pointing deflector-plate, a curved guide plate formed as anintegral extension of said deflector-plate adjacent the apertured partof said jet pipe and lying outside the jet pipe to define a path for theworking fluid changing smoothly from the rearward direction to athrustspoiling direction, and pivotal mounting means for said combineddeflector-plate and guide-plate permitting movement of the upstream endof the deflector-plate into the pipe and progressivel across the saidstream to positions in which it progressively decreases thecross-section of the rearwardly-directed jet While at the same timeproviding a path for some of the working fluid rearwardly along thedeflector-plate and then along the guide-plate into the thrust-spoilingdirection.

5. In an aircraft gas-turbine plant fitted with a jet pipe for therearward efilux of a stream of the working fluid asa propulsive jet,said jet pipe having at least one apertured part therein andthrust-spoiling means associated with said jet pipe, comprising, incombination, an upstream pointing deflector-plate, a plurality of curvedguide-plates formed as an integral extension of said deflector-plateadjacent the apertured part of said jet pipe and disposed around theoutside of the jet pipe to define for the working fluid, a path disposedaround the jet pipe changing smoothly from a rearward direction to athrust-spoiling direction, and pivotal mounting means for each of saidcombinations of deflectorplate and guide-plate, permitting movement ofthe upstream end of each deflector-plate into the pipe and progressivelydecreases the crosssection of the rearwardly-directed jet while at thesame time providing a path for some of the Working fluid rearwardlyalong the deflectorplate and then along the guide-plate into thethrust-spoiling direction.

6. In an aircraft gas-turbine plant fitted with a jet pipe for therearward efliux of a stream of working fluid as a propulsive jet, andthrustspoiling means associated with said jet pipe, comprising, incombination, a wall outside said jet pipe deflning an outer passagebetween said wall and said jet pipe, a deflector located at the forwardend of the outer passage, guide means lying outside said jet pipe todefine a path, which is a rearward continuation of the outer passage,for the Working fluid changing smoothly from rearward direction to athrust-spoiling direction, said guide means having its exit end directedradially outwardly and located adjacent said wall forming a terminus forthe rearward end of said wall, and means moving the upstream end of saiddeflector into and progressive- 1y across said jet pipe to positions inwhich it progressively decreases the cross-section of the rearwardlydirected stream of working fluid, while at the same time deflecting someof the working fluid into said outer passage.

7. In an aircraft gas-turbine plant, fitted with a jet pipe and aco-axial rearward extension of said jet pipe for the rearward efliux ofa stream of the working fluid as a propulsive jet, said extension beingaxially m-ovable in a rearward direction to form a gap between theextension and the rest of the jet pipe, an outer larger pipe surroundingsaid extension to define therewith an outer annular passagecommunicating with the interior of the jet pipe through said gap whenthe extension is moved rearwardly, guide means at the rear end of saidouter annular passage deflning a path for the working fluid chang ingsmoothly from the rearward direction to a thrust-spoiling direction, anda plurality of upstream-pointing deflectors each mounted for movement ofits upstream end, on rearward movement of said jet pipe extension, intoand progressively across the said stream to positions in which itprogressively decreases the crosssection of the rearwardly-directed jetWhile at the same time deflecting some of the working fluid into saidouter passage.

8. In an aircraft gas-turbine plant, the combination as set forth inclaim 7, wherein a part of said guide means is attached to said movablejet pipe extension to constitute a sliding door movable rearwardly withsaid jet pipe extension to vent said outer annular passage toatmosphere.

9. In an aircraft gas-turbine plant, the combination as set forth inclaim 1, and a hollow body in said set pipe around which said jet streamnormally flows, an end portion of said hollow body being movablerearwardly away from the main portion of said hollow body to form saidguide means and said deflectors locate-d upstream of said end portionand being movable into the jet stream to positions in which itprogressively decreases the cross-section of the rearwardly-directed jetwhile at the same time defleeting some of the working fluid into saidhollow body end portion.

ARTHUR RYNYON DEVEREUX ROBSON.

ALEXANDER PEARCE J OHN STONE.

References Gil-ted in the file Of this patent UNITED STATES PATENTSNumber Name Date 340,237 Nagel et al. 1 Apr. 20, 1886 1,306,913 KitchenJune 17, 1919 1,344,518 Rees June 22, 1920 1,415,705 Rees May .9, 19221,572 812 Rees 1 Feb. 9, 1926 1,714,917 Martin May 28, 1929 2,094,707Jones Oct. 5, 1937 2,396,911 Anxionnaz et a1. Mar. 19, 19 16 2,418,488Thompson Apr. 8, 1947 FOREIGN PATENTS Number Country Date 14,631 GreatBritain July 15, 1905 103,325 Great Britain Jan. 19, 1917 580,174Germany July 6, 1933

